1. Field of Endeavor
The present invention relates to a combustor for a gas turbine, particularly for a gas turbine having sequential combustion.
2. Brief Description of the Related Art
A gas turbine with sequential combustion is known to improve the efficiency of a gas turbine. This is achieved by increasing the turbine inlet temperature. In a sequential combustion gas turbine engine, fuel is burnt in a first combustor and the hot combustion gases are passed through a first turbine and subsequently supplied to a secondary combustor into which additional fuel is introduced. The combustion of the hot gases and the fuel is completed in the secondary combustor and the exhaust gases are subsequently supplied to the low pressure turbine. The secondary combustor has a mixing region where fuel is introduced and mixed with the combustion gases, and a downstream combustion region. The two regions are defined by a combustor wall having a combustion front panel positioned generally between the mixing and combustion regions.
The secondary combustor is known in the art as an SEV (Sequential EnVironmental) combustor and the first combustor is known as EV (EnVironmental) or AEV (Advanced EnVironmental) combustor. Partly due to the introduction of hydrogen (H2) rich syngas fuels, which have higher flame speeds and temperatures, there is a requirement to reduce emissions, particularly of NOx, which are produced under these conditions.